PEARLS— MOTHER OP PEARL. 65 



early Spanish settlers gave, and is of doubtful 

 meaning. 



" Shells of this family have their center of 

 distribution in Australian and adjacent seas. 

 Quantities abound upon the coast of Japan, 

 where they are known as ' AwaM.'' Other 

 names by which they are often called are ear- 

 shell,, green ear, Omer shell, etc. 



" Saliotis splendens and H. tuberculata are 

 the names science has given to the beauties 

 you have in your hands, Tom. 



" An enormous traffic is carried on in these 

 shells so useful in delicate inlaying, in lacquer, 

 and other ornamental work. The animals in- 

 habiting these palaces are considerably sought 

 after for food, while fine pearls have been 

 found within the mantle of some. The irides- 

 cent tints of these shells are produced by the 

 fluid secretion with which the interior of the 

 shells are lined ; this hardens quickly and be- 

 comes TMcre, presenting a beautifully smooth 

 and polished surface to the tender body of the 

 animal within. They are also due to the ex- 

 cessively thin laminations, irregularly overlap- 

 ping, laid on in delicate semitransparent fllm;j. 

 The thinner the laminations of this nacre mem- 

 brane the more transparent, and hence the 

 more lustrous and beautiful, the shell. 



